Imaging devices such as inkjet printers typically operate one or more printheads that are configured to eject ink for marking media. In direct marking printers, the ink is applied directly to the media, rather than to an intermediate printing surface. The media can be, for example, a surface of a continuous web of media material, a series of media sheets, or other surfaces that are desirably marked. A printhead controller typically controls the one or more printheads by generating a firing signal with reference to image data.
High speed printing systems are typically configured as continuous web printers in which a supply of media is provided in a large roll that is unwound by one or more actuators that pull media from the roll and propel it through the printing system. The web passes an arrangement of printheads that eject ink or other materials onto the media as the web passes the printheads to form images on the web. Two or more printheads can be mounted to a support structure to form an array of printheads that extends across the web in a cross-process direction. In these printers, printhead arrays are arranged in the process direction, which is the direction in which the web moves past the printhead arrays, and which is perpendicular to the cross-process direction.
These high speed printers are sometimes operated in environments that produce significant amounts of dirt or debris. The debris can be particularly significant in manufacturing environments in which the print media is a fibrous mat that is printed with adhesives or other materials. The fibers released from the web into the air can come to rest on the faces of the printheads where they can mix with ink or other materials being ejected by the printheads and remain. Some of these fibers can block nozzles in the faceplate of the printheads and adversely impact the operational status of the ejectors in the printheads. In previously known printers, the printing process would be stopped and the printheads cleaned to remove the fibers from the printheads. Such workflow stoppage is not well tolerated in manufacturing environments where the printing process can be expected to be operating 99% of the time during an eight hour run.
What is needed is a way of operating the printer so the printhead faces can be cleaned from time to time without adversely impacting the productivity of the printer.